Ivan Centamori explains how the venerable Simple Mail Transfer Protocol works and why it is so long-lived and still nearly like it was decades ago.

[...] it is not the latest JavaScript framework born last night and already obsolete this morning. No. It is persistence. It is the ability of certain technologies to remain immobile while the world around them swirls madly.

https://centamori.com/index.php?slug=smtp-protocol&lang=en

#smtp #email #protocol

A Major Mail Provider Demonstrate They Likely Do Not Understand Mail At All https://nxdomain.no/~peter/they_do_not_understand_mail_at_all.html (tracked https://bsdly.blogspot.com/2026/01/a-major-mail-provider-demonstrate-they.html)

#greytrapping #spam, #antispam #greylisting #blocklist, #openbsd #freebsd #smtp #email #SMTP, #contentfiltering #SPF #DMARC #security #networking

Heh. Looks like the tracked version of Why 451 is Good for You - Greylisting Perspectives From the Early Noughties https://nxdomain.no/~peter/why_451_is_good.html (tracked https://bsdly.blogspot.com/2025/12/why-451-is-good-for-you-greylisting.html) hit hackernews: https://news.ycombinator.com/item?id=46414653

No, I willl not respond to those comments either :D

#greylisting #greytrapping #spam #spamtrapping #antispam #spamd #openbsd #smtp

Why 451 is Good for You - Greylisting Perspectives From the Early Noughties https://nxdomain.no/~peter/why_451_is_good.html (tracked https://bsdly.blogspot.com/2025/12/why-451-is-good-for-you-greylisting.html) @nostarch #greytrapping #greylisting #smtp #email #spam #antispam #bookofpf

I find it really amuzing that IT-departments around the world is just plainly copying the example DNS-records in my blog-posts about DMARC.

Resulting in me getting reports about their domain to my inbox

#dmarc #email #smtp

I have an enforcing #DMARC policy set up on my personal email domain. I use #DMARCAnalyzer for processing aggregate reports from servers that send them. Every week I log in and check to make sure everything's fine, i.e., (a) there isn't a significant uptick of people forging emails from my domain that I should look into (unlikely), and (b) I haven't broken something stupid in my infrastructure and caused my own outbound emails to violate my policy.
#SMTP #emailAdmin #sysAdmin (1/2)